
//
// Authors:
//   Atsushi Enomoto
//
// Copyright 2007 Novell (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
#if NET_2_0

using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Xml;

namespace System.Xml.Linq
{

	public abstract class XContainer : XNode
	{

		internal XContainer()
		{
		}
		XNode first;
		XNode last;

		public XNode FirstNode
		{
			get { return first; }

			internal set { first = value; }
		}

		public XNode LastNode
		{
			get { return last; }

			internal set { last = value; }
		}

		void CheckChildType(object o, bool addFirst)
		{
			if (o == null || o is string || o is XNode)
				return;
			if (o is IEnumerable)
			{

				foreach (object oc in ((IEnumerable)o))
					CheckChildType(oc, addFirst);
				return;
			}
			else
				throw new ArgumentException("Invalid child type: " + o.GetType());
		}

		public void Add(object content)
		{
			if (content == null)
				return;

			foreach (object o in XUtil.ExpandArray(content))
			{
				if (!OnAddingObject(o, false, last, false))
				{
					var node = XUtil.ToNode(o);
					OnAddingObject(node);
					AddNode(node);
					OnAddedObject(node);
				}
			}
		}

		void AddNode(XNode n)
		{
			CheckChildType(n, false);
			n = (XNode)XUtil.GetDetachedObject(n);
			n.SetOwner(this);
			if (first == null)
				last = first = n;
			else
			{
				last.NextNode = n;
				n.PreviousNode = last;
				last = n;
			}
		}

		public void Add(params object[] content)
		{
			if (content == null)
				return;

			foreach (object o in XUtil.ExpandArray(content))
				Add(o);
		}

		public void AddFirst(object content)
		{
			if (first == null)
				Add(content);
			else
				first.AddBeforeSelf(XUtil.ExpandArray(content));
		}

		public void AddFirst(params object[] content)
		{
			if (content == null)
				return;
			if (first == null)
				Add(content);
			else

				foreach (object o in XUtil.ExpandArray(content))
					if (!OnAddingObject(o, false, first.PreviousNode, true))
						first.AddBeforeSelf(o);
		}

		internal virtual bool OnAddingObject(object o, bool rejectAttribute, XNode refNode, bool addFirst)
		{
			return false;
		}

		public XmlWriter CreateWriter()
		{
			return new XNodeWriter(this);
		}

		public IEnumerable<XNode> Nodes()
		{
			XNode next;

			for (XNode n = FirstNode; n != null; n = next)
			{
				next = n.NextNode;
				yield return n;
			}
		}

		public IEnumerable<XNode> DescendantNodes()
		{

			foreach (XNode n in Nodes())
			{
				yield return n;
				XContainer c = n as XContainer;
				if (c != null)

					foreach (XNode d in c.DescendantNodes())
						yield return d;
			}
		}

		public IEnumerable<XElement> Descendants()
		{

			foreach (XNode n in DescendantNodes())
			{
				XElement el = n as XElement;
				if (el != null)
					yield return el;
			}
		}

		public IEnumerable<XElement> Descendants(XName name)
		{

			foreach (XElement el in Descendants())
				if (el.Name == name)
					yield return el;
		}

		public IEnumerable<XElement> Elements()
		{

			foreach (XNode n in Nodes())
			{
				XElement el = n as XElement;
				if (el != null)
					yield return el;
			}
		}

		public IEnumerable<XElement> Elements(XName name)
		{

			foreach (XElement el in Elements())
				if (el.Name == name)
					yield return el;
		}

		public XElement Element(XName name)
		{

			foreach (XElement el in Elements())
				if (el.Name == name)
					return el;
			return null;
		}

		internal void ReadContentFrom(XmlReader reader, LoadOptions options)
		{

			while (!reader.EOF)
			{
				if (reader.NodeType == XmlNodeType.EndElement)
					// end of the element.
					break;
				Add(XNode.ReadFrom(reader, options));
			}
		}

		public void RemoveNodes()
		{

			foreach (XNode n in Nodes())
				n.Remove();
		}

		public void ReplaceNodes(object content)
		{
			// First, it creates a snapshot copy, then removes the contents, and then adds the copy. http://msdn.microsoft.com/en-us/library/system.xml.linq.xcontainer.replacenodes.aspx
			if (FirstNode == null)
			{
				Add(content);
				return;
			}
			var l = new List<object>();

			foreach (var obj in XUtil.ExpandArray(content))
				l.Add(obj);
			RemoveNodes();
			Add(l);
		}

		public void ReplaceNodes(params object[] content)
		{
			ReplaceNodes((object)content);
		}
	}
}

#endif